Subsample
Purpose
Description
Macro Synopsis
Modules
Related Functions
References
Purpose
Subsampling of a signal
Description
"Subsample" creates a new signal with a new scale n times
greater than the current scale by taking only every nth sample
out of the given signal. This procedure is called subsampling (or
decimation, i.e. the opposite of interpolation). It reduces the
amount of data but may lead to a loss of information if the
reciprocal of the new scale is less than 2 times the highest
frequency contained in the original signal.
If this is the case, you should select the anti-aliasing option.
Parameters of "Subsample" therefore are
- the subsampling factor n and
- the anti-aliasing flag antialias which is either
- "No" or 0 for a pure subsampling or
- "Yes" or 1 if you wish the resulting signal to be
averaged, i.e. that the resulting data are each the average
of n consecutive original data values.
Macro Synopsis
y = SubSample(x,n,antialias);
signal x,y;
int n;
option antialias;
Modules
Student, Professional
Related Functions
Envelope, Resample,
Unwrap, Wrap.
References
Oppenheim/Schafer [3]